v4.19.13 snapshot.
diff --git a/net/sctp/bind_addr.c b/net/sctp/bind_addr.c
new file mode 100644
index 0000000..7df3704
--- /dev/null
+++ b/net/sctp/bind_addr.c
@@ -0,0 +1,557 @@
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2001, 2003
+ * Copyright (c) Cisco 1999,2000
+ * Copyright (c) Motorola 1999,2000,2001
+ * Copyright (c) La Monte H.P. Yarroll 2001
+ *
+ * This file is part of the SCTP kernel implementation.
+ *
+ * A collection class to handle the storage of transport addresses.
+ *
+ * This SCTP implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This SCTP implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *    La Monte H.P. Yarroll <piggy@acm.org>
+ *    Karl Knutson          <karl@athena.chicago.il.us>
+ *    Jon Grimm             <jgrimm@us.ibm.com>
+ *    Daisy Chang           <daisyc@us.ibm.com>
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/in.h>
+#include <net/sock.h>
+#include <net/ipv6.h>
+#include <net/if_inet6.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+/* Forward declarations for internal helpers. */
+static int sctp_copy_one_addr(struct net *net, struct sctp_bind_addr *dest,
+			      union sctp_addr *addr, enum sctp_scope scope,
+			      gfp_t gfp, int flags);
+static void sctp_bind_addr_clean(struct sctp_bind_addr *);
+
+/* First Level Abstractions. */
+
+/* Copy 'src' to 'dest' taking 'scope' into account.  Omit addresses
+ * in 'src' which have a broader scope than 'scope'.
+ */
+int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
+			const struct sctp_bind_addr *src,
+			enum sctp_scope scope, gfp_t gfp,
+			int flags)
+{
+	struct sctp_sockaddr_entry *addr;
+	int error = 0;
+
+	/* All addresses share the same port.  */
+	dest->port = src->port;
+
+	/* Extract the addresses which are relevant for this scope.  */
+	list_for_each_entry(addr, &src->address_list, list) {
+		error = sctp_copy_one_addr(net, dest, &addr->a, scope,
+					   gfp, flags);
+		if (error < 0)
+			goto out;
+	}
+
+	/* If there are no addresses matching the scope and
+	 * this is global scope, try to get a link scope address, with
+	 * the assumption that we must be sitting behind a NAT.
+	 */
+	if (list_empty(&dest->address_list) && (SCTP_SCOPE_GLOBAL == scope)) {
+		list_for_each_entry(addr, &src->address_list, list) {
+			error = sctp_copy_one_addr(net, dest, &addr->a,
+						   SCTP_SCOPE_LINK, gfp,
+						   flags);
+			if (error < 0)
+				goto out;
+		}
+	}
+
+out:
+	if (error)
+		sctp_bind_addr_clean(dest);
+
+	return error;
+}
+
+/* Exactly duplicate the address lists.  This is necessary when doing
+ * peer-offs and accepts.  We don't want to put all the current system
+ * addresses into the endpoint.  That's useless.  But we do want duplicat
+ * the list of bound addresses that the older endpoint used.
+ */
+int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
+			const struct sctp_bind_addr *src,
+			gfp_t gfp)
+{
+	struct sctp_sockaddr_entry *addr;
+	int error = 0;
+
+	/* All addresses share the same port.  */
+	dest->port = src->port;
+
+	list_for_each_entry(addr, &src->address_list, list) {
+		error = sctp_add_bind_addr(dest, &addr->a, sizeof(addr->a),
+					   1, gfp);
+		if (error < 0)
+			break;
+	}
+
+	return error;
+}
+
+/* Initialize the SCTP_bind_addr structure for either an endpoint or
+ * an association.
+ */
+void sctp_bind_addr_init(struct sctp_bind_addr *bp, __u16 port)
+{
+	INIT_LIST_HEAD(&bp->address_list);
+	bp->port = port;
+}
+
+/* Dispose of the address list. */
+static void sctp_bind_addr_clean(struct sctp_bind_addr *bp)
+{
+	struct sctp_sockaddr_entry *addr, *temp;
+
+	/* Empty the bind address list. */
+	list_for_each_entry_safe(addr, temp, &bp->address_list, list) {
+		list_del_rcu(&addr->list);
+		kfree_rcu(addr, rcu);
+		SCTP_DBG_OBJCNT_DEC(addr);
+	}
+}
+
+/* Dispose of an SCTP_bind_addr structure  */
+void sctp_bind_addr_free(struct sctp_bind_addr *bp)
+{
+	/* Empty the bind address list. */
+	sctp_bind_addr_clean(bp);
+}
+
+/* Add an address to the bind address list in the SCTP_bind_addr structure. */
+int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
+		       int new_size, __u8 addr_state, gfp_t gfp)
+{
+	struct sctp_sockaddr_entry *addr;
+
+	/* Add the address to the bind address list.  */
+	addr = kzalloc(sizeof(*addr), gfp);
+	if (!addr)
+		return -ENOMEM;
+
+	memcpy(&addr->a, new, min_t(size_t, sizeof(*new), new_size));
+
+	/* Fix up the port if it has not yet been set.
+	 * Both v4 and v6 have the port at the same offset.
+	 */
+	if (!addr->a.v4.sin_port)
+		addr->a.v4.sin_port = htons(bp->port);
+
+	addr->state = addr_state;
+	addr->valid = 1;
+
+	INIT_LIST_HEAD(&addr->list);
+
+	/* We always hold a socket lock when calling this function,
+	 * and that acts as a writer synchronizing lock.
+	 */
+	list_add_tail_rcu(&addr->list, &bp->address_list);
+	SCTP_DBG_OBJCNT_INC(addr);
+
+	return 0;
+}
+
+/* Delete an address from the bind address list in the SCTP_bind_addr
+ * structure.
+ */
+int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
+{
+	struct sctp_sockaddr_entry *addr, *temp;
+	int found = 0;
+
+	/* We hold the socket lock when calling this function,
+	 * and that acts as a writer synchronizing lock.
+	 */
+	list_for_each_entry_safe(addr, temp, &bp->address_list, list) {
+		if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
+			/* Found the exact match. */
+			found = 1;
+			addr->valid = 0;
+			list_del_rcu(&addr->list);
+			break;
+		}
+	}
+
+	if (found) {
+		kfree_rcu(addr, rcu);
+		SCTP_DBG_OBJCNT_DEC(addr);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+/* Create a network byte-order representation of all the addresses
+ * formated as SCTP parameters.
+ *
+ * The second argument is the return value for the length.
+ */
+union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
+					 int *addrs_len,
+					 gfp_t gfp)
+{
+	union sctp_params addrparms;
+	union sctp_params retval;
+	int addrparms_len;
+	union sctp_addr_param rawaddr;
+	int len;
+	struct sctp_sockaddr_entry *addr;
+	struct list_head *pos;
+	struct sctp_af *af;
+
+	addrparms_len = 0;
+	len = 0;
+
+	/* Allocate enough memory at once. */
+	list_for_each(pos, &bp->address_list) {
+		len += sizeof(union sctp_addr_param);
+	}
+
+	/* Don't even bother embedding an address if there
+	 * is only one.
+	 */
+	if (len == sizeof(union sctp_addr_param)) {
+		retval.v = NULL;
+		goto end_raw;
+	}
+
+	retval.v = kmalloc(len, gfp);
+	if (!retval.v)
+		goto end_raw;
+
+	addrparms = retval;
+
+	list_for_each_entry(addr, &bp->address_list, list) {
+		af = sctp_get_af_specific(addr->a.v4.sin_family);
+		len = af->to_addr_param(&addr->a, &rawaddr);
+		memcpy(addrparms.v, &rawaddr, len);
+		addrparms.v += len;
+		addrparms_len += len;
+	}
+
+end_raw:
+	*addrs_len = addrparms_len;
+	return retval;
+}
+
+/*
+ * Create an address list out of the raw address list format (IPv4 and IPv6
+ * address parameters).
+ */
+int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
+			   int addrs_len, __u16 port, gfp_t gfp)
+{
+	union sctp_addr_param *rawaddr;
+	struct sctp_paramhdr *param;
+	union sctp_addr addr;
+	int retval = 0;
+	int len;
+	struct sctp_af *af;
+
+	/* Convert the raw address to standard address format */
+	while (addrs_len) {
+		param = (struct sctp_paramhdr *)raw_addr_list;
+		rawaddr = (union sctp_addr_param *)raw_addr_list;
+
+		af = sctp_get_af_specific(param_type2af(param->type));
+		if (unlikely(!af)) {
+			retval = -EINVAL;
+			sctp_bind_addr_clean(bp);
+			break;
+		}
+
+		af->from_addr_param(&addr, rawaddr, htons(port), 0);
+		if (sctp_bind_addr_state(bp, &addr) != -1)
+			goto next;
+		retval = sctp_add_bind_addr(bp, &addr, sizeof(addr),
+					    SCTP_ADDR_SRC, gfp);
+		if (retval) {
+			/* Can't finish building the list, clean up. */
+			sctp_bind_addr_clean(bp);
+			break;
+		}
+
+next:
+		len = ntohs(param->length);
+		addrs_len -= len;
+		raw_addr_list += len;
+	}
+
+	return retval;
+}
+
+/********************************************************************
+ * 2nd Level Abstractions
+ ********************************************************************/
+
+/* Does this contain a specified address?  Allow wildcarding. */
+int sctp_bind_addr_match(struct sctp_bind_addr *bp,
+			 const union sctp_addr *addr,
+			 struct sctp_sock *opt)
+{
+	struct sctp_sockaddr_entry *laddr;
+	int match = 0;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+		if (!laddr->valid)
+			continue;
+		if (opt->pf->cmp_addr(&laddr->a, addr, opt)) {
+			match = 1;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return match;
+}
+
+/* Does the address 'addr' conflict with any addresses in
+ * the bp.
+ */
+int sctp_bind_addr_conflict(struct sctp_bind_addr *bp,
+			    const union sctp_addr *addr,
+			    struct sctp_sock *bp_sp,
+			    struct sctp_sock *addr_sp)
+{
+	struct sctp_sockaddr_entry *laddr;
+	int conflict = 0;
+	struct sctp_sock *sp;
+
+	/* Pick the IPv6 socket as the basis of comparison
+	 * since it's usually a superset of the IPv4.
+	 * If there is no IPv6 socket, then default to bind_addr.
+	 */
+	if (sctp_opt2sk(bp_sp)->sk_family == AF_INET6)
+		sp = bp_sp;
+	else if (sctp_opt2sk(addr_sp)->sk_family == AF_INET6)
+		sp = addr_sp;
+	else
+		sp = bp_sp;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+		if (!laddr->valid)
+			continue;
+
+		conflict = sp->pf->cmp_addr(&laddr->a, addr, sp);
+		if (conflict)
+			break;
+	}
+	rcu_read_unlock();
+
+	return conflict;
+}
+
+/* Get the state of the entry in the bind_addr_list */
+int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
+			 const union sctp_addr *addr)
+{
+	struct sctp_sockaddr_entry *laddr;
+	struct sctp_af *af;
+	int state = -1;
+
+	af = sctp_get_af_specific(addr->sa.sa_family);
+	if (unlikely(!af))
+		return state;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+		if (!laddr->valid)
+			continue;
+		if (af->cmp_addr(&laddr->a, addr)) {
+			state = laddr->state;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return state;
+}
+
+/* Find the first address in the bind address list that is not present in
+ * the addrs packed array.
+ */
+union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr	*bp,
+					const union sctp_addr	*addrs,
+					int			addrcnt,
+					struct sctp_sock	*opt)
+{
+	struct sctp_sockaddr_entry	*laddr;
+	union sctp_addr			*addr;
+	void 				*addr_buf;
+	struct sctp_af			*af;
+	int				i;
+
+	/* This is only called sctp_send_asconf_del_ip() and we hold
+	 * the socket lock in that code patch, so that address list
+	 * can't change.
+	 */
+	list_for_each_entry(laddr, &bp->address_list, list) {
+		addr_buf = (union sctp_addr *)addrs;
+		for (i = 0; i < addrcnt; i++) {
+			addr = addr_buf;
+			af = sctp_get_af_specific(addr->v4.sin_family);
+			if (!af)
+				break;
+
+			if (opt->pf->cmp_addr(&laddr->a, addr, opt))
+				break;
+
+			addr_buf += af->sockaddr_len;
+		}
+		if (i == addrcnt)
+			return &laddr->a;
+	}
+
+	return NULL;
+}
+
+/* Copy out addresses from the global local address list. */
+static int sctp_copy_one_addr(struct net *net, struct sctp_bind_addr *dest,
+			      union sctp_addr *addr, enum sctp_scope scope,
+			      gfp_t gfp, int flags)
+{
+	int error = 0;
+
+	if (sctp_is_any(NULL, addr)) {
+		error = sctp_copy_local_addr_list(net, dest, scope, gfp, flags);
+	} else if (sctp_in_scope(net, addr, scope)) {
+		/* Now that the address is in scope, check to see if
+		 * the address type is supported by local sock as
+		 * well as the remote peer.
+		 */
+		if ((((AF_INET == addr->sa.sa_family) &&
+		      (flags & SCTP_ADDR4_PEERSUPP))) ||
+		    (((AF_INET6 == addr->sa.sa_family) &&
+		      (flags & SCTP_ADDR6_ALLOWED) &&
+		      (flags & SCTP_ADDR6_PEERSUPP))))
+			error = sctp_add_bind_addr(dest, addr, sizeof(*addr),
+						   SCTP_ADDR_SRC, gfp);
+	}
+
+	return error;
+}
+
+/* Is this a wildcard address?  */
+int sctp_is_any(struct sock *sk, const union sctp_addr *addr)
+{
+	unsigned short fam = 0;
+	struct sctp_af *af;
+
+	/* Try to get the right address family */
+	if (addr->sa.sa_family != AF_UNSPEC)
+		fam = addr->sa.sa_family;
+	else if (sk)
+		fam = sk->sk_family;
+
+	af = sctp_get_af_specific(fam);
+	if (!af)
+		return 0;
+
+	return af->is_any(addr);
+}
+
+/* Is 'addr' valid for 'scope'?  */
+int sctp_in_scope(struct net *net, const union sctp_addr *addr,
+		  enum sctp_scope scope)
+{
+	enum sctp_scope addr_scope = sctp_scope(addr);
+
+	/* The unusable SCTP addresses will not be considered with
+	 * any defined scopes.
+	 */
+	if (SCTP_SCOPE_UNUSABLE == addr_scope)
+		return 0;
+	/*
+	 * For INIT and INIT-ACK address list, let L be the level of
+	 * of requested destination address, sender and receiver
+	 * SHOULD include all of its addresses with level greater
+	 * than or equal to L.
+	 *
+	 * Address scoping can be selectively controlled via sysctl
+	 * option
+	 */
+	switch (net->sctp.scope_policy) {
+	case SCTP_SCOPE_POLICY_DISABLE:
+		return 1;
+	case SCTP_SCOPE_POLICY_ENABLE:
+		if (addr_scope <= scope)
+			return 1;
+		break;
+	case SCTP_SCOPE_POLICY_PRIVATE:
+		if (addr_scope <= scope || SCTP_SCOPE_PRIVATE == addr_scope)
+			return 1;
+		break;
+	case SCTP_SCOPE_POLICY_LINK:
+		if (addr_scope <= scope || SCTP_SCOPE_LINK == addr_scope)
+			return 1;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+int sctp_is_ep_boundall(struct sock *sk)
+{
+	struct sctp_bind_addr *bp;
+	struct sctp_sockaddr_entry *addr;
+
+	bp = &sctp_sk(sk)->ep->base.bind_addr;
+	if (sctp_list_single_entry(&bp->address_list)) {
+		addr = list_entry(bp->address_list.next,
+				  struct sctp_sockaddr_entry, list);
+		if (sctp_is_any(sk, &addr->a))
+			return 1;
+	}
+	return 0;
+}
+
+/********************************************************************
+ * 3rd Level Abstractions
+ ********************************************************************/
+
+/* What is the scope of 'addr'?  */
+enum sctp_scope sctp_scope(const union sctp_addr *addr)
+{
+	struct sctp_af *af;
+
+	af = sctp_get_af_specific(addr->sa.sa_family);
+	if (!af)
+		return SCTP_SCOPE_UNUSABLE;
+
+	return af->scope((union sctp_addr *)addr);
+}